US 8,025,049 B2Granted

High efficiency furnace having a blower housing with an enlarged air outlet opening

AssigneeRbc Horizon, Inc.

InventorSteven W. Post

Life of this patent

Estimating the term…

Loading patent…

Abstract

An air distribution blower housing for a furnace is designed with an enlarged air outlet opening that slows down and spreads out the air flow from the blower housing over a greater area of the furnace heat exchanger. The blower housing thereby enables less air pressure drop through the heat exchanger, which increases the efficiency of the blower motor operation. The design of the blower housing also efficiently turns the velocity head of the air flow through the housing to usable static air pressure at the housing air outlet. The enlarged air outlet opening of the blower housing is achieved without increasing the exterior diameter dimensions of the blower housing by utilizing a volute outer wall of the blower housing that has an exponentially increasing expansion angle in the direction of air flow through the blower housing.

Claims51

Dependent claims

A high efficiency furnace comprising:

a furnace enclosure having an interior volume and a distribution air outlet opening on the enclosure that is adapted for communication with an air distribution system;
a primary heat exchanger in the furnace enclosure interior volume, the primary heat exchanger being adjacent the distribution air outlet opening;
a secondary heat exchanger in the furnace enclosure interior volume, the secondary heat exchanger being adjacent the primary heat exchanger and being separate from the primary heat exchanger;
a fan wheel in the furnace enclosure interior volume, the fan wheel having an outer diameter dimension, an axis of rotation that defines mutually perpendicular axial and radial directions, and the fan wheel being rotatable in a rotation direction around the axis of rotation;
a blower housing in the furnace enclosure interior volume, the blower housing having an interior volume containing the fan wheel and an air flow outlet opening positioned adjacent the secondary heat exchanger to direct a flow of air from the blower housing interior volume through the air flow outlet opening, then through the secondary heat exchanger, then through the primary heat exchanger, then through the furnace enclosure distribution air outlet opening, the blower housing having first and second side walls on axially opposite ends of the fan wheel and on opposite sides of the air flow outlet opening, and the blower housing having an outer wall between the first and second side walls, the outer wall having a volute portion that spirals away from the fan wheel axis of rotation as it extends from a first end of the volute portion at one side of the air flow outlet opening around the blower housing interior volume to a second end of the volute portion at an opposite side of the air flow outlet opening from the first end, and the blower housing outer wall having a radial dimension from the fan wheel axis of rotation to the second end of the outer wall that is at least 0.91 times the fan wheel outer diameter dimension, and the blower housing air outlet opening having a minimal radial dimension that is at least 0.73 times the fan wheel outer diameter dimension.

2 more elements

A high efficiency furnace comprising:

a furnace enclosure having an interior volume and a distribution air outlet opening on the furnace enclosure that is adapted for communication with an air distribution system;
a primary heat exchanger in the furnace enclosure interior volume, the primary heat exchanger being adjacent the distribution air outlet opening;
a secondary heat exchanger in the furnace enclosure interior volume, the secondary heat exchanger being adjacent the primary heat exchanger and being separate from the primary heat exchanger;
a fan wheel in the furnace enclosure interior volume, the fan wheel having an outer diameter dimension and a circumference dimension, the fan wheel having a center axis of rotation that defines mutually perpendicular axial and radial directions and the fan wheel being rotatable about the center axis of rotation in a rotation direction;
a blower housing in the furnace enclosure interior volume, the blower housing containing the fan wheel and having an air outlet opening positioned adjacent the secondary heat exchanger to direct a flow of air from the air outlet opening through the secondary heat exchanger, then through the primary heat exchanger and then through the distribution air outlet opening of the furnace enclosure, the air outlet opening having a minimum radial dimension, a ratio of the minimum radial dimension and the fan wheel outer diameter dimension being at least 0.73, the blower housing having an outer wall with a volute shaped portion having a length that extends from a first end of the volute shaped portion around the fan wheel in the rotation direction to a second end of the volute shaped portion, the first end of the volute shaped portion being spaced radially a first distance dimension from the fan wheel axis of rotation and the second end of the volute shaped portion being spaced radially a second distance dimension from the fan wheel axis of rotation that is larger than the first distance, a ratio of the second distance dimension and the fan wheel outer diameter dimension being at least 0.91, and the volute shaped portion of the blower housing outer wall having a generally increasing expansion angle as the volute shaped portion extends in the rotation direction around the fan wheel.

2 more elements

A furnace comprising:

a furnace enclosure having an interior volume and a distribution air outlet opening on the furnace enclosure that is adapted for communication with an air distribution system;
a primary heat exchanger in the furnace enclosure interior volume, the primary heat exchanger being adjacent the distribution air outlet opening;
a fan wheel in the furnace enclosure interior volume, the fan wheel having an outer diameter dimension and a circumference dimension, the fan wheel having a center axis of rotation that defines mutually perpendicular axial and radial directions and the fan wheel being rotatable about the center axis of rotation in a rotation direction;
a blower housing in the furnace enclosure interior volume, the blower housing containing the fan wheel and having an air outlet opening positioned adjacent the primary heat exchanger to direct a flow of air from the air outlet opening through the primary heat exchanger and then through the distribution air outlet opening of the furnace enclosure, the air outlet opening having a minimum radial dimension, a ratio of the minimum radial dimension and the fan wheel outer diameter dimension being at least 0.73, the blower housing having an outer wall with a volute shaped portion having a length that extends from a first end of the volute shaped portion around the fan wheel in the rotation direction to a second end of the volute shaped portion, the first end of the volute shaped portion being spaced radially a first distance dimension from the fan wheel axis of rotation and the second end of the volute shaped portion being spaced radially a second distance dimension from the fan wheel axis of rotation that is larger than the first distance, a ratio of the second distance dimension and the fan wheel outer diameter dimension being at least 0.91, and the volute shaped portion of the blower housing outer wall having a generally increasing expansion angle as the volute shaped portion extends in the rotation direction around the fan wheel.

1 more element

A furnace comprising:

a furnace enclosure having an interior volume and a distribution air outlet opening on the furnace enclosure that is adapted for communication with an air distribution system;
a primary heat exchanger in the furnace enclosure interior volume, the primary heat exchanger being adjacent the distribution air outlet opening;
a fan wheel in the furnace enclosure interior volume, the fan wheel having an outer diameter dimension and a circumference dimension, the fan wheel having a center axis of rotation that defines mutually perpendicular axial and radial directions and the fan wheel being rotatable about the center axis of rotation in a rotation direction;
a blower housing in the furnace enclosure interior volume, the blower housing containing the fan wheel and having an air outlet opening positioned adjacent the primary heat exchanger to direct a flow of air from the air outlet opening through the primary heat exchanger and then through the distribution air outlet opening of the furnace enclosure, the air outlet opening having a minimum radial dimension, a ratio of the minimum radial dimension and the fan wheel outer diameter dimension being at least 0.73, the blower housing having an outer wall with a volute shaped portion having a length that extends from a first end of the volute shaped portion around the fan wheel in the rotation direction to a second end of the volute shaped portion, the first end of the volute shaped portion being spaced radially a first distance dimension from the fan wheel axis of rotation and the second end of the volute shaped portion being spaced radially a second distance dimension from the fan wheel axis of rotation that is larger than the first distance, and the volute shaped portion of the blower housing outer wall having a generally increasing expansion angle as the volute shaped portion extends in the rotation direction around the fan wheel from the first end to the second end of the volute shaped portion.

1 more element

A furnace comprising:

a furnace enclosure having an interior volume and a distribution air outlet opening on the furnace enclosure that is adapted for communication with an air distribution system;
a primary heat exchanger in the furnace enclosure interior volume, the primary heat exchanger being adjacent the distribution air outlet opening;
a fan wheel in the furnace enclosure interior volume, the fan wheel having an outer diameter dimension and a circumference dimension, the fan wheel having a center axis of rotation that defines mutually perpendicular axial and radial directions and the fan wheel being rotatable about the center axis of rotation in a rotation direction;
a blower housing in the furnace enclosure interior volume, the blower housing containing the fan wheel and having an air outlet opening positioned adjacent the primary heat exchanger to direct a flow of air from the air outlet opening through the primary heat exchanger and then through the distribution air outlet opening of the furnace enclosure, the air outlet opening having a minimum radial dimension, a ratio of the minimum radial dimension and the fan wheel outer diameter dimension being at least 0.73, the blower housing having an outer wall with a volute shaped portion having a length that extends from a first end of the volute shaped portion around the fan wheel in the rotation direction to a second end of the volute shaped portion, the first end of the volute shaped portion being spaced radially a first distance dimension from the fan wheel axis of rotation and the second end of the volute shaped portion being spaced radially a second distance dimension from the fan wheel axis of rotation that is larger than the first distance, and a ratio of the second distance dimension and the fan wheel outer diameter dimension being at least 0.91.

1 more element

An air handler comprising:

an enclosure having an interior volume and a distribution air outlet opening on the enclosure that is adapted for communication with an air distribution system;
a temperature transfer means in the enclosure interior volume, the temperature transfer means being adjacent the distribution air outlet opening;
a fan wheel in the enclosure interior volume, the fan wheel having an outer diameter dimension and a circumference dimension, the fan wheel having a center axis of rotation that defines mutually perpendicular axial and radial directions and the fan wheel being rotatable about the center axis of rotation in a rotation direction;
a blower housing in the enclosure interior volume, the blower housing containing the fan wheel and having an air outlet opening positioned adjacent the temperature transfer means to direct a flow of air from the air outlet opening through the temperature transfer means and then through the distribution air outlet opening of the enclosure, the air outlet opening having a minimum radial dimension, a ratio of the minimum radial dimension and the fan wheel outer diameter dimension being at least 0.73, the blower housing having an outer wall with a volute shaped portion having a length that extends from a first end of the volute shaped portion around the fan wheel in the rotation direction to a second end of the volute shaped portion, the first end of the volute shaped portion being spaced radially a first distance dimension from the fan wheel axis of rotation and the second end of the volute shaped portion being spaced radially a second distance dimension from the fan wheel axis of rotation that is larger than the first distance, a ratio of the second distance dimension and the fan wheel outer diameter dimension being at least 0.91, and the volute shaped portion of the blower housing outer wall having a generally increasing expansion angle as the volute shaped portion extends in the rotation direction around the fan wheel.

1 more element

An air handler comprising:

an enclosure having an interior volume and a distribution air outlet opening on the enclosure that is adapted for communication with an air distribution system;
a temperature transfer means in the enclosure interior volume, the temperature transfer means being adjacent the distribution air outlet opening;
a fan wheel in the enclosure interior volume, the fan wheel having an outer diameter dimension and a circumference dimension, the fan wheel having a center axis of rotation that defines mutually perpendicular axial and radial directions and the fan wheel being rotatable about the center axis of rotation in a rotation direction;
a blower housing in the enclosure interior volume, the blower housing containing the fan wheel and having an air outlet opening, the blower housing having an outer wall with a length that extends from a first end of the length around the fan wheel in the rotation direction to the second end of the length, the first end of the length being spaced radially a first distance dimension from the fan wheel axis of rotation and the second end of the length being spaced radially a second distance dimension from the fan wheel axis of rotation that is larger than the first distance, the air outlet opening being between the first and second ends of the outer wall length, the air outlet opening having a minimum dimension between the first and second ends of the outer wall length, and a ratio of the minimum dimension and the fan wheel outer diameter dimension being at least 0.73.

1 more element

Dependencies are inferred from the claim text.